An electro-photographic image forming apparatus forms an image by transferring a developing agent image held on an image carrier, such as a photosensitive drum, to a recording medium, such as a recording sheet.
Provided that not all the developing agent held on the photosensitive drum is transferred to the recording sheet and that some of the developing agent still remains on the photosensitive drum, the residual developing agent may be transferred to the sheet during the next image forming operation.
Therefore, for instance, Japanese unexamined patent application publication No. JP-A-2002-72602 describes a related art image forming apparatus. In the related art image forming apparatus, there is provided a cleaning roller that is applied with a voltage opposite in polarity to the developing agent held on the photosensitive drum, and a developing agent remaining on the photosensitive drum is recovered by the cleaning roller.